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<a name="Derived-Types-and-struct"></a>
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Next: <a href="Interoperable-Global-Variables.html#Interoperable-Global-Variables" accesskey="n" rel="next">Interoperable Global Variables</a>, Previous: <a href="Intrinsic-Types.html#Intrinsic-Types" accesskey="p" rel="prev">Intrinsic Types</a>, Up: <a href="Interoperability-with-C.html#Interoperability-with-C" accesskey="u" rel="up">Interoperability with C</a> &nbsp; [<a href="index.html#SEC_Contents" title="Table of contents" rel="contents">Contents</a>][<a href="Option-Index.html#Option-Index" title="Index" rel="index">Index</a>]</p>
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<a name="Derived-Types-and-struct-1"></a>
<h4 class="subsection">6.1.2 Derived Types and struct</h4>
<a name="index-C-derived-type-and-struct-interoperability"></a>
<a name="index-derived-type-interoperability-with-C"></a>
<a name="index-interoperability_002c-derived-type-and-struct"></a>

<p>For compatibility of derived types with <code>struct</code>, use
the <code>BIND(C)</code> attribute in the type declaration.  For instance, the
following type declaration
</p>
<div class="smallexample">
<pre class="smallexample"> USE ISO_C_BINDING
 TYPE, BIND(C) :: myType
   INTEGER(C_INT) :: i1, i2
   INTEGER(C_SIGNED_CHAR) :: i3
   REAL(C_DOUBLE) :: d1
   COMPLEX(C_FLOAT_COMPLEX) :: c1
   CHARACTER(KIND=C_CHAR) :: str(5)
 END TYPE
</pre></div>

<p>matches the following <code>struct</code> declaration in C
</p>
<div class="smallexample">
<pre class="smallexample"> struct {
   int i1, i2;
   /* Note: &quot;char&quot; might be signed or unsigned.  */
   signed char i3;
   double d1;
   float _Complex c1;
   char str[5];
 } myType;
</pre></div>

<p>Derived types with the C binding attribute shall not have the <code>sequence</code>
attribute, type parameters, the <code>extends</code> attribute, nor type-bound
procedures.  Every component must be of interoperable type and kind and may not
have the <code>pointer</code> or <code>allocatable</code> attribute.  The names of the
components are irrelevant for interoperability.
</p>
<p>As there exist no direct Fortran equivalents, neither unions nor structs
with bit field or variable-length array members are interoperable.
</p>



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